FIELD OF THE INVENTION
The present invention relates to a method for separating a blood material into blood components by centrifugation. More particularly, the present invention is concerned with a method for separating a blood material into blood components by centrifugation, wherein a multiple blood bag unit, which includes a plurality of flexible blood bags (at least one of the flexible blood bags containing a blood material) liquid-tightly connected to at least one leukocyte-removing filter device through flexible tubes in a predetermined order, is accommodated in a centrifuge bucket of a centrifugal apparatus in which the centrifuge bucket is swingably attached to a rotor fixedly connected to a rotation shaft, and the rotation shaft is rotated to rotate the rotor and turn and orient the centrifuge bucket in a direction of a centrifugal force exerted, thereby performing separation of the blood material into blood components by centrifugation, and wherein when the multiple blood bag unit is accommodated in the centrifuge bucket, at least the blood material-containing flexible blood bag or bags are inserted in the centrifuge bucket while placing at least the leukocyte-removing filter device outside of the centrifuge bucket, wherein the leukocyte-removing filter device is directly or indirectly secured relative to the rotor and a center of the filter device is located at a distance from an axis of the rotation shaft which is smaller than a distance between a pivotal axis of the turning of the centrifuge bucket and an axis of the rotation shaft at a portion thereof which has the rotor connected thereto.
The present invention is also concerned with a centrifugal apparatus for practicing the method of the present invention.
By the method and apparatus of the present invention, the centrifugal force to be sustained by the filter device is reduced to a minimum due to the location of the filter device at a reduced distance from the rotation shaft, so that the danger of damaging or adversely affecting the filter device due to the centrifugal force is extremely reduced or eliminated. Further, since the filter device is placed outside of the centrifuge bucket, the centrifuge bucket can have an enough room for accommodating the blood bags. Therefore, not only can insertion of the blood bags into and taking-out thereof from the centrifuge bucket be readily performed with no difficulty, but also, even when the filter device has an angular portion or a projection, there is no danger of damaging the filter device and the blood bags due to a pressure-contact of the angular portion or projection of the filter device with the blood bags.